Dw. Burt et al., THE CHICKEN TRANSFORMING GROWTH FACTOR-BETA-3 GENE - GENOMIC STRUCTURE, TRANSCRIPTIONAL ANALYSIS, AND CHROMOSOMAL LOCATION, DNA and cell biology, 14(2), 1995, pp. 111-123
In this paper, we report the isolation, characterization, and mapping
of the chicken transforming growth factor-beta 3 (TGF-beta 3) gene. Th
e gene contains seven exons and six introns spanning 16-kb of the chic
ken genome. A comparison of the 5'-flanking regions of human and chick
en TGF-beta 3 genes reveals two regions of sequence conservation. The
first contains ATF/CRE and TBP/TATA sequence motifs within an 87-bp re
gion. The second is a 162-bp region with no known sequence motifs. Ide
ntification of transcription start sites using chicken RNA isolated fr
om various embryonic and adult tissues reveals two sites of initiation
, P1 and P2, which map to these two conserved regions. Comparison of 3
'-flanking regions of chicken and mammalian TGF-beta 3 genes also reve
aled conserved sequences, The most significant homologies were found i
n the 3'-most end of the transcribed region. DNA sequence analysis of
chicken TGF-beta 3 cDNAs isolated by 3'-RACE revealed multiple polyade
nylation sites unusually distant from a poly(A) signal motif. A Mse I
restriction fragment length polymorphism (RFLP) marker was used to map
the TGFB3 locus to linkage group E7 on the East Lansing reference bac
kcross. Linkage to the TH locus showed that the TGFB3 locus was physic
ally located on chicken chromosome 5.